Evaluating soil erosion by water in a small alpine catchment in Northern Italy: comparison of empirical models

To quantify water erosion rates and annual soil loss in mountainous areas, two different empirical models were used to estimate the effects of soil erosion in a small mountain basin, the Guerna Creek watershed, located in the Central Southern Alps (Northern Italy). These two models, Revised Universal Soil Loss Equation (RUSLE) and Erosion Potential Model (EPM), were implemented in a Geographical Information System, accounting for the geographical, geomorphological, and weather-climate parameters, which are fundamental to evaluating the intensity and variability of the erosive processes. Soil characterization was supported by laboratory analysis. The results (computed soil loss of 87 t/ha/year and 11.1 m3/ha/year, using RUSLE equation and EPM method, respectively, and sediment yield of 7.5 m3/ha/year using EPM method) were compared to other studies reported in the literature for different case studies with similar topographic and climatic features, as well as to those provided by the European Soil Data Centre (ESDAC). In both cases, the agreement was satisfactory, showing consistency of the adopted procedures to the parametrization of the physical processes.